I haven't read the page, but I would guess they're trying to highlight how a real package manager works, compared to the cool-kids toy tool Homebrew.

Given that there are Mac using developers, who somehow think Homebrew is a good tool, and then want Homebrew for Linux so they can use it there, because they have no fucking idea what a real package manager is like, I don't blame them for wanting to highlight how powerful Apt is.